Google Wallet, like its name implies, attempts to replace your wallet — well, the credit cards in it at least. On first glance, paying for purchases with your phone just sounds cool, though some could consider it to be more a gimmick than a ground-breaking, game changing app.

Imagine being able to either hook up your existing credit card, or sign up for a pre-paid credit card through your online Google Wallet account (which recently replaced Google Checkout). The killer-app functionality comes from being able to show you your real-time account balance — taking into account the transactions that you’ve made that may not have cleared yet. Compared to traditional credit cards which require you to keep your own ledger so you don’t spend too much, this is nothing short of amazing!

To sweeten the deal, Google’s even giving you ten bucks just to try it out!

To use Google Wallet (the app) you’ve got to have a phone with an NFC chip. No problemo! The Nexus S and Galaxy Nexus (to name a couple) already come with NFC capabilities. When I picked up my Galaxy Nexus, Google Wallet was literally the first app I went to install.

I searched for the app on my phone: not found?

I found the app on market.android.com and eagerly hit the “Install” button. “Not available on your carrier.” What? Why does my carrier matter? Oh well, no problem, I’ll just pull the SIM and install over WiFi. No good: Google’s smarter than that!

What’s even worse, not even the Nexus S is compatible with Google Wallet, you’ve got to have the Nexus S 4G on Sprint to get Google Wallet. Well, that’s not entirely true, you can hack a version onto your non-Sprint Nexus S, and some (few) have even reported success getting the app to work on their Galaxy Nexus. But it’s a dirty hack, and technically violates Google’s terms of use which says you’re not permitted to use it on devices or carriers that it’s not “officially” supported on.

And then there’s the part about being only available in the US.

So although Google Wallet is available for a few people, most of us can’t have it — yet.